websockets transactions events metrics

[cfaur09]

Reasoning

• Need visibility into total WebSocket events at cluster level
• Missing basic counters for core WebSocket operations. (transactionsCompleted, transactionsPendingResults, onBatchUpdated

Proposed Changes

• Added three simple counters:
• websocket_transactions_completed_total
• websocket_transactions_pending_results_total
• websocket_batch_updates_total

How to test

• <localhost:4001>/metrics

[github-actions]

k6 load testing comparison.
Base Commit Hash: 8135bf8
Target Commit Hash: 471468b

Metric	Base				Target				Diff
	Avg	Max	90	95	Avg	Max	90	95	Avg	Max	90	95
Accounts	47.08	224.61	51.07	52.61	51.26	1250.94	54.14	55.49	+8.86% 🔴	+456.94% 🔴	+6.01% 🔴	+5.48% 🔴
Mex	47.46	502.80	51.05	52.52	50.47	674.04	54.15	55.42	+6.33% 🔴	+34.06% 🔴	+6.08% 🔴	+5.51% 🔴
Pool	47.12	281.43	51.09	52.58	49.77	196.10	54.12	55.39	+5.63% 🔴	-30.32% ✅	+5.93% 🔴	+5.35% 🔴
Nodes	47.69	845.36	51.05	52.51	49.61	140.83	54.10	55.37	+4.02% 🔴	-83.34% ✅	+5.98% 🔴	+5.45% 🔴
Transactions	60.12	1281.06	51.54	53.43	67.01	2298.84	54.54	56.34	+11.46% 🔴	+79.45% 🔴	+5.83% 🔴	+5.43% 🔴
Tokens	46.85	110.08	51.02	52.48	50.17	499.48	54.16	55.43	+7.09% 🔴	+353.74% 🔴	+6.15% 🔴	+5.61% 🔴
Blocks	52.54	1021.65	51.43	53.57	56.57	1236.38	54.53	56.42	+7.68% 🔴	+21.02% 🔴	+6.04% 🔴	+5.32% 🔴
Test Run Duration	60003.77				60003.60

Legend: Avg - Average Response Time, Max - Maximum Response Time, 90 - 90th Percentile, 95 - 95th Percentile
All times are in milliseconds.